Amp Problems :(

[Bo~Select@]

I have a problem with my amp - when I switch the system on I get a Thump from the sub and a even bigger one when I switch it off. It also does it when I change audio sources e.g. Radio to CDC.

This evening I tried

A new set of RCA leads from the head Unit - Away from any power leads

A new Remote lead - Away from the power leads

About 5 Different earth points - and a different earth lead

Its a kenwood 350 Watt amp with a JL 12" sub - Never had a problem with these in my last car.

The problem started last night - I did take the amp apart to fix a loose RCA conector (which I did fine) The system has been in the car a few weeks.

I'm Stumped

 

[Dan]

Souns like the amps arnt being momentarily disabled while you switch buttons, or its completely switching off. If youve tried the remote wire. Get someone to look at the amp light when you change channel...

 

[Bo~Select@]

Cheers D4NS - Will have someone have a look.

By the way - It does not do it when the RCA's are disconected - It will do it with either RCA plugged in.


I did try a Different set of RCAs - no good though

 

[Dan]

It does the same with a house stereo if you dont switch the amp off before you turn the player off. Have you got y vonnectors on your RCA's?

 

[Bo~Select@]

It does the same with a house stereo if you dont switch the amp off before you turn the player off. Have you got y vonnectors on your RCA's?

Yeah - Like a house system - Great big Thump through the sub ... I'm thinking a may have buggered the amp up.


Errrrr .... whats a Vonnector?

 

[Dan]

Ill take that as a no. Its a signal splitter cable that turns 2 channels into 4. Is it doing it with the front as well or just the sub?

 

[Bo~Select@]

Nope, Its a mono amp - Two RCAs in - One cable out ... The rest of the speakers seem fine but they are on cross overs (HPF on the head unit).

 

[Bo~Select@]

I swapped the amp over this evening - Still no Joy :bang:

 

[Bo~Select@]

Tracked the problem down to the head unit - Its only doing it when its on the sub out channel - If I plug it into the other Amp outs its good as gold.

Must be a short in the Sub out somewhere.

 

[Neo-The Matrix]

So it seems that the headunit is not lowering the gain for the sub channel cause you to hear the thump.

Guess you have to try a different HU then. There exist so called speakers protectors that eliminate the thump but I do not recall if they can be used on subs cause of the power.

 

[Bo~Select@]

I tried a ground loop isolator ... No joy...